Chair base



Oct. 25, 19 w. H. KAFFERLIN ETAL 3,281,105

CHAIR BASE Filed Aug. 18, 1965 INVENTORS United States Patent 3,281,105 CHAIR BASE William H. Kafferlin, Spring Creek, and James H. Armstrong, Corry, Pa., assignors to Corry Jamestown Corporation, Corry, Pa., a corporation of New York Filed Aug. 18, 1965, Ser. No. 480,607 2 Claims. (Cl. 248188.7)

This invention relates generally to chairs and, more particularly, to the kind of chairs known as swivel chairs and consists of the novel and peculiar construction and combination of chair base, arrangement of parts, and various details of construction which will be more fully hereinafter set forth.

It is an object of this invention to provide an improved swivel chair base which requires :a minimum amount of maintenance and is simple in construction, economical to manufacture, simple and eflicient to use, and selflubricating.

Another object of the invention is to provide an improved swivel chair base.

Another object is to provide a chair base utilizing a swivel bushing that is made of a self-lubricating material.

With the above and other objects in view, the present invention consists of the combination and arrangement of parts hereinaftermore fully described, illustrated in the accompanying drawing and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportions, and minor details of construction, without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawing:

FIG. 1 is an isometric view of a chair base according to the invention; and

FIG. 2 is a cross sectional view of the chair base shown in FIG. 1.

Now with more particular reference to the drawing, the chair base shown has a support shaft 11, which may be fixed to a chair seat such as that indicated generally in the drawing in phantom line. The support shaft may be threaded and the collar 18 may be threaded onto the support shaft, if desired, in a conventional manner.

The center hub 12 is fixed to the legs 20 by welding or other fastening means. Hub 12 extends to the lower edge of legs 20. Sleeve rests on top of legs 20 and washer 21 overlies hub 12 and is welded to sleeve 10. The legs 20 radiate outwardly from the center hub 12, and a suitable structural arrangement may be provided to hold the legs 20 securely to the center hub 12.

The bushing 13 is pressed into the hub 12. The bushing may be made of a self-lubricating plastic, for example, Delrin, nylon, or polyethylene. The bushing 13 has a flange member made up of the first flange 16 and the second flange 14 spaced from each other and defining a groove 15 therebetween. Flange 16 rests on washer 21. The groove 15 receives a screw 19, which is threadably received in the collar 18. An indexing washer 17 is supported between the flanged cup member 18 and the upper flange 14, so that the washer 17 carries the thrust exerted by the weight of a person on the chair supported by support shaft 11 and engages detents in collar 18 to provide rotation with the shaft 11 in a conventional manner. The washer 17 and the collar 18 normally rotate with respect to the flange 14. Collar 18 must rotate with the shaft 11 or the height adjustment will change.

The legs have suitable casters thereon as indicated that may be received in suitable structure at the outer end of the legs 20, as shown. The legs 20 may be made in 3,281,105 Patented Oct. 25, 1966 any suitable way, for example, they may be fabricated from two U-sections, which may be welded to the hub 12 at the inner end and have the caster supports disposed in suitable brackets at their outer end. Reinforcing ribs 22 are fixed to legs 20.

In ope-ration, a chair indicated by the phantom lines may be fixed to the upper end of the support shaft 11, and the flange 18 may be adjusted on the shaft to hold the seat above the floor at the desired distance. Then the screw 19 will be inserted in the groove 15 to prevent the shaft 11 from coming out of bushing 13 when the chair is lifted. Thus, the chair can rotate relative to the base and the self-lubricating material of flange 14 will reduce friction between the bushing 13 and shaft 11 to a minimum and will allow the chair to rotate freely and noiselessy relative to the base.

The foregoing specification sets forth the invention in its preferred practical forms but the structure shown is capable of modification within a range of equivalents without departing from the invention which is to be understood is broadly novel as is commensurate with the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A chair base and support shaft combination comprising a hollow cylindrical hub,

spaced legs integrally attached to said hub and radiating therefrom,

said hub extending from the lower edges of said legs to a position spaced above said legs,

means on the distal ends of said legs to engage a supporting surface,

a hollow cylindrical sleeve concentrically received on said hub,

one end of said sleeve resting on said legs,

a washer overlying one end of said hub and attached to said sleeve,

a hollow bushing,

said bushing being received in said hub,

a first flange on said bushing,

said first flange resting on said washer,

a support shaft rotatably received in said bushing,

means to attach a chair to said support shaft,

a collar on said support shaft,

a second flange on said bushing,

said collar resting on said second flange,

said bushing being made of a self-lubricating plastic.

2. The chair base recited in claim 1 wherein said collar is cup shaped,

said cup shaped collar receives said bushing,

said first flange and said second flange being spaced from each other defining a peripheral groove therebetween,

and screw means in said collar received in said peripheral groove.

References Cited by the Examiner UNITED STATES PATENTS 2,065,699 12/1936 Herold 248188.1 2,746,705 5/1956 McKinley 248l88.7 2,992,803 7/1961 Good 248l88.7 3,059,888 10/1962 Lie 248415 X 3,148,855 9/1964 Hamilton 248l88.7 3,188,033 6/1965 Groves 248l88.7

CLAUDE A. LE ROY, Primary Examiner.

R. P. SEITTER, Assistant Examiner. 

1. A CHAIR BASE AND SUPPORT SHAFT COMBINATION COMPRISING A HOLLOW CYLINDRICAL HUB, SPACED LEGS INTERGRALLY ATTACHED TO SAID HUB AND RADIATING THEREFROM, SAID HUB EXTENDING FROM THE LOWER EDGES OF SAID LEGS TO A POSITION SPACED ABOVE SAID LEGS, MEANS ON THE DISTAL ENDS OF SAID LEGS TO ENGAGE A SUPPORTING SURFACE, A HOLLOW CYLINDRICAL SLEEVE CONCENTRICALLY RECEIVED ON SAID HUB, ONE END OF SAID SLEEVE RESTING ON SAID LEGS, A WASHER OVERLYING ONE END OF SAID HUB AND ATTACHED TO SAID SLEEVE, A HOLLOW BUSHING, SAID BUSHING BEING RECEIVED IN SAID HUB, A FIRST FLANGE ON SAID BUSHING, SAID FIRST FLANGE RESTING ON SAID WASHER, A SUPPORT SHAFT ROTATABLY RECEIVED IN SAID BUSHING, MEANS TO ATTACH A CHAIR TO SAID SUPPORT SHAFT, A COLLAR ON SAID SUPPORT SHAFT, A SECOND FLANGE ON SAID BUSHING, SAID COLLAR RESTING ON SAID SECOND FLANGE, SAID BUSHING BEING MADE OF A SELF-LUBRICATING PLASTIC. 